C64-dev/reference/vic-registers.md

VIC-II Register Map — Quick Reference

VIC-II base address: $D000 (53248)

Offset	Address	Dec	Name	Description
+0	$D000	53248	SP0X	Sprite 0 X position
+1	$D001	53249	SP0Y	Sprite 0 Y position
+2	$D002	53250	SP1X	Sprite 1 X
+3	$D003	53251	SP1Y	Sprite 1 Y
+4	$D004	53252	SP2X	Sprite 2 X
+5	$D005	53253	SP2Y	Sprite 2 Y
+6	$D006	53254	SP3X	Sprite 3 X
+7	$D007	53255	SP3Y	Sprite 3 Y
+8	$D008	53256	SP4X	Sprite 4 X
+9	$D009	53257	SP4Y	Sprite 4 Y
+A	$D00A	53258	SP5X	Sprite 5 X
+B	$D00B	53259	SP5Y	Sprite 5 Y
+C	$D00C	53260	SP6X	Sprite 6 X
+D	$D00D	53261	SP6Y	Sprite 6 Y
+E	$D00E	53262	SP7X	Sprite 7 X
+F	$D00F	53263	SP7Y	Sprite 7 Y
+10	$D010	53264	MSIGX	Sprites X MSB (bit N = sprite N X bit 8)
+11	$D011	53265	SCROLY	Vertical scroll/control
+12	$D012	53266	RASTER	Raster counter / IRQ line
+13	$D013	53267	LPENX	Light pen X (read-only)
+14	$D014	53268	LPENY	Light pen Y (read-only)
+15	$D015	53269	SPENA	Sprite enable (bit N)
+16	$D016	53270	SCROLX	Horizontal scroll/control
+17	$D017	53271	YXPAND	Sprite Y expansion (bit N)
+18	$D018	53272	VMCSB	Memory control (screen/char base)
+19	$D019	53273	VICIRQ	IRQ status (read/ack)
+1A	$D01A	53274	IRQMSK	IRQ mask enable
+1B	$D01B	53275	SPBGPR	Sprite-BG priority
+1C	$D01C	53276	SPMC	Sprite multicolor enable
+1D	$D01D	53277	XXPAND	Sprite X expansion
+1E	$D01E	53278	SPSPCL	Sprite-sprite collision (clears on read)
+1F	$D01F	53279	SPBGCL	Sprite-BG collision (clears on read)
+20	$D020	53280	EXTCOL	Border color
+21	$D021	53281	BGCOL0	Background color 0
+22	$D022	53282	BGCOL1	Background color 1
+23	$D023	53283	BGCOL2	Background color 2
+24	$D024	53284	BGCOL3	Background color 3
+25	$D025	53285	SPMC0	Sprite multicolor 0
+26	$D026	53286	SPMC1	Sprite multicolor 1
+27	$D027	53287	SP0COL	Sprite 0 color
+28	$D028	53288	SP1COL	Sprite 1 color
+29	$D029	53289	SP2COL	Sprite 2 color
+2A	$D02A	53290	SP3COL	Sprite 3 color
+2B	$D02B	53291	SP4COL	Sprite 4 color
+2C	$D02C	53292	SP5COL	Sprite 5 color
+2D	$D02D	53293	SP6COL	Sprite 6 color
+2E	$D02E	53294	SP7COL	Sprite 7 color

$D011 — SCROLY Bit Fields

Bit	Name	Description
7	RST8	Raster line bit 8
6	ECM	Extended Color Mode
5	BMM	Bitmap Mode
4	DEN	Display Enable
3	RSEL	Row select: 1=25 rows, 0=24 rows
2-0	YSCL	Vertical fine scroll (0-7)

$D016 — SCROLX Bit Fields

Bit	Name	Description
4	MCM	Multicolor Mode
3	CSEL	Column select: 1=40 cols, 0=38 cols
2-0	XSCL	Horizontal fine scroll (0-7)

$D018 — VMCSB Memory Control

Bits	Name	Description
7-4	VM	Screen RAM base: value × $0400 within VIC bank
3-1	CB	Char set base: value × $0800 within VIC bank

Default $10: screen at $0400, chars at $1000 (ROM mirror in bank 0).

$D019 — VICIRQ / $D01A — IRQMSK

Bit	Event
3	Light pen
2	Sprite-BG collision
1	Sprite-sprite collision
0	Raster IRQ

To acknowledge: read $D019, then write the value back (write-1-to-clear).